Vulvar cancer occurs in the vulva, the external genital area of a woman's reproductive system. It can affect any part of the vulva, including the labia, the mons pubis (the skin and tissue that cover the pubic bone), the clitoris, or the vaginal or urethral openings. In most cases, it affects the inner edges of the labia majora or labia minora.
The vast majority of vulvar cancers are squamous cell carcinomas. This cancer starts in squamous cells, the main type of skin cells. Squamous cell cancer usually develops over many years. Before it forms, abnormal cells usually develop in the surface layer of the skin, called the epithelium. This condition is called vulvar intraepithelial neoplasia (VIN).
Another common form of vulvar cancer is melanoma. It usually occurs on the labia minora or the clitoris. Uncommon forms of vulvar cancer include Bartholin's gland adenocarcinoma and non-mammary Paget's disease. Few vulvar cancers are sarcomas. These cancers occur in the connective tissue beneath the skin.
Vulvar cancer is uncommon, accounting for a very small percentage of all cancers in women. Most women diagnosed with vulvar cancer are older than 50; and two-thirds are older than 70.
Recently, younger women have been getting diagnosed with VIN. With early detection and treatment of this precancerous condition, a woman may never develop actual vulvar cancer.
Risk factors for vulvar cancer include
having abnormal, precancerous vulvar cells
being infected with human papilloma virus (HPV)
having a condition related to immune deficiency (an organ transplant, for example)
having vulvar dystrophy, a condition in which skin looks abnormal and is covered with white bumps
having precancerous changes to the vulva
having precancerous changes on the cervix or a history of cervical cancer
being of northern European ancestry.